From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-x22f.google.com (mail-pg0-x22f.google.com [IPv6:2607:f8b0:400e:c05::22f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 457F23BA8E for ; Mon, 21 May 2018 17:15:13 -0400 (EDT) Received: by mail-pg0-x22f.google.com with SMTP id k2-v6so6897757pgc.1 for ; Mon, 21 May 2018 14:15:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=gym312/Lh2zsDC8Xie47zPOV41EzSuGAHO16ssbzuC8=; b=e+mXxoVhHTEhAvH4fb3UXKCmZv4Wk/9R5kcCyO9X9ZJWY1mcxNcQKkDPwtcuZk6R8M mhJ/lbgk2NoTuVyftAgWiiYV170mi3xS6j3UgNGRX6+FyRRdIGe6YfXokSsKafRwKlku oB7Q8bSaHlJtHZI5InR2xCj7kAT5BaFwqKTXcyQyGcT68RSZmsdyWCQUlf6LRUwcd56g Emah+cUqBg3Q/2rMPMtI/+ke2QBr6/Kd1vtiuYyrTRmlMCNbRwYCdmCykW2HEA2FanIe LEztLPANV3EfIgQI3yidx8PdeStRardrNK3OWMaJxeIMLsR4rvgmk4kPrDXCEi0buMhT PnCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=gym312/Lh2zsDC8Xie47zPOV41EzSuGAHO16ssbzuC8=; b=YVfxYlR622NZUZ+47tiad6rwmJoek1ygURRQKOP123ks6bI6HMu7JmeP3ph2ErXnob yR3N0+2pjOtYpniVVw+07hj4qmFmlhj+9/Za4HFPq6G797mjHjvn0i5+GPbpAcj+QgtB sTBiMhXC123k/rr662DvPIjaJxcIpj2T0436aGC7lUhGlhC0AN07YVkjTK5nHrPuTfFZ ePEUM6POWMT49kByWa9x9UTwAt7QV82LJx+Z4ZQ9ESF19ae5iQ1duO6VsfB2iYUVqACE /d0sEpxdIIiKB9i9hYftK4DeXzTBXPwRUd2wivLIX7WAO/aZW95Vu8rqoBexxRWiX/pw dwIw== X-Gm-Message-State: ALKqPwet2auv7A3oc9h+tvKyMT8zv3538gH5Q6PAmAKvYZdSKQDhiNhk BKSkZrtuqto0NXQj6NJ1S8g= X-Google-Smtp-Source: AB8JxZrAaHQGCqflHLaB9b9SwJmc0zV2g3/Z57NnWHI6XDdlpZrV4WuhGyZVHcASOZWtKCg+cg2kJw== X-Received: by 2002:a63:7f13:: with SMTP id a19-v6mr9621831pgd.444.1526937312483; Mon, 21 May 2018 14:15:12 -0700 (PDT) Received: from ?IPv6:2620:15c:2c1:200:55c7:81e6:c7d8:94b? ([2620:15c:2c1:200:55c7:81e6:c7d8:94b]) by smtp.gmail.com with ESMTPSA id p84-v6sm31759389pfi.66.2018.05.21.14.15.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 21 May 2018 14:15:11 -0700 (PDT) To: =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= , netdev@vger.kernel.org, cake@lists.bufferbloat.net Cc: Yuchung Cheng , Neal Cardwell References: <152693459693.32668.4272129427997495747.stgit@alrua-kau> <152693495862.32668.11914023983598526087.stgit@alrua-kau> From: Eric Dumazet Message-ID: <92cf4a80-8e26-8a08-1b8f-e8f0c131e9e6@gmail.com> Date: Mon, 21 May 2018 14:15:11 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <152693495862.32668.11914023983598526087.stgit@alrua-kau> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [Cake] [PATCH net-next v14 3/7] sch_cake: Add optional ACK filter X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 May 2018 21:15:13 -0000 On 05/21/2018 01:35 PM, Toke Høiland-Jørgensen wrote: > + > + /* 3 reserved flags must be unset to avoid future breakage > + * ECE/CWR/NS can be safely ignored > + * ACK must be set > + * All other flags URG/PSH/RST/SYN/FIN must be unset > + * 0x0FFF0000 = all TCP flags (confirm ACK=1, others zero) > + * 0x01C00000 = NS/CWR/ECE (safe to ignore) > + * 0x0E3F0000 = 0x0FFF0000 & ~0x01C00000 > + */ > + if (((tcp_flag_word(tcph) & > + cpu_to_be32(0x0E3F0000)) != TCP_FLAG_ACK)) > + return false; > Why ECE/CWR/NS can be ignored ? DCTCP would disagree, and maybe BBR soon.